The guayule shrub is a well-known source of natural rubber (also called polyisoprene). This shrub stores rubber within the individual cells of the plant (e.g., stems, roots or leaves). While precise amounts may vary depending upon age of the shrub, growing conditions and species, the guayule shrub generally contains 1-10 weight percent rubber. Processes for removing the rubber from the guayule shrub generally entail extraction of rubber and resin from the shrub and the creation of a large amount of waste material which is primarily non-soluble woody material (commonly referred to as bagasse).